Improvement in plates for artificial teeth



Nr/TELD raras an 1 rauen.

GEORGE H. HURD, OF ST. LOUIS, MISSOURI.

Specification forming part 0f Letters Patent No. 57,7%5, dated September 4, 1866.

To all whom tt 'may concern:

Be it known that I, GEORGE H. Hum), or St. Y Louis, in the county ot' St. Louis and State of Missouri, have invented certain new and useful Improvements in Articial Teeth; andI do hereby declare that the following is a full and clear description thereof, reference being had to the accompanying' drawings, and to the letters of reference marked thereon.

Figure l ct' the accompanying dran-'ings is a perspective view ot' a set of artificial teeth, prepared in the improved manner. Fig. 2 is a plan of a similar set. Fig. 3 is a sectional elevation taken on the line .fr a' in Fig. 2.

The nature ot' this invention consists in a new and improved construction of the plate into which the artificial teeth are inserted.

It has been, up to the present time, the universal diction ot' tiental works and the established practice ot' all dental surgeons to round oft' the lower portions ot' the plate where it joins up to the jaw. Chapin A. Harris, an eminent dental writer and established authority ot'onr own country, says: Out awav the plate until you think yo'u'have spoiled it.77

There is little or no difficulty in litting teeth to and retaining them in the superior jaw, since the employment otl a suction-plate coverin g the entire roof of the mouth has been introduced.

As the tongue occupies the entire space in the inferior jaw, no such appliance can be introduced, and consequently springs and various other appliances have been adopted to remedy the dit'culty, but frequently without avail, as it sometimes happens the alveolar ridge, which is usually depended upon tohold the teeth in place, is so much absorbed as to be scarcely perceptible and is covered over with the integuments of the lower jaw lying in loose folds upon it. In cases ot" this kind it has always been extremely ditiicult to tit and secure artiticial teeth, and Harris says that it would be better in cases ot' this kind wholly to dispense with their use.

It is to overcome these diftieulties and to tit any mouth, however badly shaped, with an easy-wearing and serviceable set ot' teeth; and I propose to do it upon an entirely new principle-that is, by widening out the bottom part ot the plate into a flange instead ot' rounding it oft, as formerly. The said flange will t out tightly to the lip, the muscles of which will draw tightly over it and tend to hold it in place, and at the same time will prevent the passage of air under the plate, s0 that if the air be once sucked out from under the plate by the wearer the teeth may beheld in place in either jaw by what is now called the suction principle,77 as applied to the superior jaw.

To enable those skilled in the art to make and use my improved artificial teeth, I will proceed to describe their construction and operation.

The teeth A are inserted into the plate Bin the usual manner. The latter may be formed ot' any material known to dental art.

Instead ot' rounding oft orcntting away the bottoni ot the plate, as above described, it will be widened out into the flanges b, which will act against the lips and in the suction manner, as already recited. There may be suctioncavities b', as shown by dotted lines in Fig'. 2, in the bottom ot the said iianges and extending the whole length ot' them, or the bottoms ofthe iianges may be made flat, as also shown in the drawings herewith submitted. In either ease the teeth so titted and prepared may be worn in eitherI the superior or interior jaw with the greatest ease and comfort.

The plate l5 may have its outer flange constructed ot' flexible rubber, or for tender gums the whole ot' its bearing portions may be cushioned with flexible rubber.

The inner flange will form in the inferior jaw a shelf for the tongue to lie upon, and hold it down during mastication.

Having described my invention, what I claim is* The plate B, when constructed with the fianges o, either with or without the suctioncavities l1', so that artiiicial teeth may be titted into months of bad formation and secured there either by suction or by muscular power, or by both.

GEO. H. HURD.

Witnesses:

M. RANDOLPH, GEO. l. HERTHEL, Jr. 

